 Pressurized injection nozzle for screening paste |
| It is therefore an object of the present invention to provide an improved method of applying ... |
|
| Apparatus for testing integrated circuits |
| p Accordingly, the present invention overcomes these and other disadvantages by providing apparatus ... |
|
| Handler used in testing system for semiconductor devices |
| What is claimed is: 1. A handler for supplying a semiconductor device to a test head which is ... |
|
| Wafer boat for vertical diffusion and vapor growth furnace |
| An object of the invention, therefore, is to overcome the problems existing in the prior art, and ... |
|
| Apparatus for transporting a wafer and a carrier used for the same |
| An object of the present invention is to provide a wafer transporting apparatus which is capable of ... |
|
| Semiconductor object pre-aligning method |
| The present invention includes a prealignment apparatus for semiconductor objects which minimizes ... |
|
| Fusion seal and sealing mixtures |
| My invention resides in part in a fusion seal between the surfaces of two bodies, the fusion seal ... |
|
| Wafer transfer system |
| What is claimed is: 1. In a wafer transfer system including automatic robot claws and a susceptor ... |
|
| Mail tracker with zip break marker |
| OF THE INVENTION FIG. 1 is a generalized diagrammatic illustration of a specific embodiment of a ... |
|
|
Method of etching polyimide
| Details |
Inventors: Fineman, Jonathan P.; Kieny, Jr., Leonard A.;
Assignee: International Business Machines Corporation (Armonk, NY)
Primary Examiner: Powell; William A.
Assistant Examiner:
Attorney, Agent or Firm: Hogg; William N.
In etching openings in polyimide film, the film is first etched with a basic reagent in its uncured or partially cured state to form the desired openings, and thereafter, the film is cured. However, this will leave a layer of disturbed material surrounding the openings which has absorbed some reagent and will not fully cure and, therefore, not provide topography suitable for reliable interconnection and metal adherence. This disturbed material is removed by a second etch in a basic reagent, following additional curing to a sufficient extent to prevent any etching of the polyimide free of absorbed etchant. Thereby, suitable topography and adherence is provided. |
|
DETAILED DESCRIPTION What is claimed is: 1.
A method of etching an opening in polyimide material wherein the polymide material is provided in a sufficiently uncured condition to permit etching by a basic etchant, and wherein a selected location of the uncured polyimide is exposed for etching the opening, the improvement comprising: etching said polyimide at the desired location with a basic reagent to provide the opening in the polyimide, some of said etchant being absorbed by a layer of polyimide material surrounding said opening but remaining in place, curing the polyimide to a sufficient extent to prevent any etching of the polyimide free of absorbed etchant, and etching the exposed location a second time with a basic reagent and remove the layer of polyimide having absorbed etchant, whereby the material surrounding the opening after the second etch is rednered free of absorbed etchant.
2.
The invention as defined in claim 1 wherein the reagent is selected from the group potassium hydroxide, sodium hydroxide, and tetra methyl ammonium hydroxide.
3.
The invention as defined in claim 2 wherein the reagent is potassium hydroxide.
4.
The invention as defined in claim 1 wherein the polyimide is a film on a substrate material.
5.
The invention as defined in claim 4 wherein a plurality of vias are etched in said polyimide to expose the substrate.
6.
The invention as defined in claim 1 wherein the reagent used for the second etch is the same as the reagent used for the first etch.
Description:
BACKGROUND OF THE INVENTION This invention relates generally to the etching of polyimide material, and more particularly to a method of etching polyimide to provide a surface surrounding the etched areas which has topography suitable for reliable interconnection and metal adherence.
In many different processes it is necessary to provide a polyimide film with openings therein.
For example, in the packaging of semiconductor chips polyimide films are often coated on substrates.
In certain of these uses it is necessary to form openings in the polyimide coating to allow for electrical connections to be made between various levels of metallurgy
|
|
Nonmetallic Processes 
